Method for manufacturing a corrugated corner piece or the like

ABSTRACT

A method of making a dihedron-like corrugated corner element from a metal sheet, comprising folding said sheet into a dihedron and forming therein a corrugation extending throughout transversely of the edge of the dihedron by driving in a portion of said sheet while simultaneously drawing near to each other the non-deformed sheet portions located on each side of the crest folding line of the corrugations.

United States Patent [191 Alleaume et al.

[ Nov. 13, 1973 METHOD FOR MANUFACTURING A CORRUGATED CORNER PIECE ORTHE LIKE Inventors: Jean H. Alleaume, Saint-Cloud;

Gilbert C. F. Fournier, Le Havre, both of France Assignee: Technigaz,Paris, France Filed: Oct. 15, 1971 Appl. No.: 189,574

Related U.S. Application Data Division of Ser. No. 842,482, July 17,1969, Pat. No. 3,686,920.

Foreign Application Priority Data Dec. 31, 1968 France 68182929 U.S. Cl.72/379 Int. Cl B2ld 13/02 Field of Search 72/379; 52/276;

220/9 LG; 114/74 A [56] References Cited UNlTED STATES PATENTS 3,321,8815/1967 Alleaume 52/276 3,325,953 6/1967 Alleaume..... 52/276 3,343,3979/1967 Fournier.. 72/379 3,351,441 11/1967 Gewiss 72/379 3,395,5058/1968 Lamy 72/276 Primary Examiner-Charles W. Lanham AssistantExaminer-Gene P. Crosby Att0rney Nolte & Nolte [57] ABSTRACT A method ofmaking a dihedron-like corrugated corner element from a metal sheet,comprising folding said sheet into a dihedron and forming therein acorrugation extending throughout transversely of the edge of thedihedron by driving in a portion of said sheet while simultaneouslydrawing near to each other the non-deformed sheet portions located oneach side of the crest folding line of the corrugations.

3 Claims, 3 Drawing Figures PATENTED NOV 13 I975 SHEET 10F 2 METHOD FORMANUFACTURING A CORRUGATED CORNER PIECE OR THE LIKE Ser. is a divisionof the copending U.S. patent application er. No. 842,482 filed on July17, 1969, now U.S. Pat. No. 3,686,920.

The present invention relates to and has essentially for its object amethod of manufacturing or shaping a corrugated, pleated, or ribbedsolid corner piece, generally in the shape of a dihedron or the like andof the kind disclosed in the copending divisional U.S. patentapplication Ser. No. 174,748 filed on Aug. 25, 1971, now abandoned, aswell as the various applications and uses resulting from the workingthereof.

In said copending divisional U.S. patent application has been describedand shown a one-piece corrugated corner element generally in the shapeof a dihedron formed of sheet metal and comprising at least onecorrugation projecting on the internal side and on each face of thedihedral angle, in the form of a convex folded rib at leastapproximately dihedral, extending in a longitudinal directionsubstantially at right angles to the edge of said dihedron and having auniform crosssection substantially symmetrical with respect to a planeextending at right angles to the edge of said dihedron and containingthe respective crest lines of the two corrugations of the two adjacentfaces of the dihedron. The concave-fold lines at the base of each saidcorrugation extend to the edge of said dihedron, where they meet thehomologous lines of the other corrugation and each corrugation crestline divides at its end on the one hand into two diverging lateralconvex-fold lines joining respectively the edge of said dihedron at thecorresponding points of concurrence of said concave-fold base lines, oneither side of the corrugation and, on the other hand, into a centralconcave-fold line which divides at its re-entrant end on the one handinto two diverging lateral concave-fold lines joining respectively saidpoints of concurrence and, on the other hand, into a medial convex-foldline interconnecting the respective re-entrant ends of the two mutuallyconfronting corrugations, so as to define adjacent triangularfacets'forming a common skew polyhedral surface of connection andtransition between the two corrugations, the general geometricalconfiguration being preferably developable in a plane.

Each base face or wall of the aforesaid dihedron is substantially planeand the aforesaid corrugations are substantially rectilinear andpreferably substantially symmetrical with respect to the bisecting planeof said dihedron.

Moreover, on the external side of the aforesaid dihedron there is noprojection and no protuberance of ma terial beyond the external surfaceof the wall of the said dihedron and the value of the dihedral angle ispreferably within a range of from 60 to 180.

The intermediate projecting dihedral portion interconnecting the saidtwo corrugations is provided at its center with a depression in itscrest at least-approximately dihedral extending transversely of the saidportion over at least part of the height thereof.

Hitherto a method of manufacturing or shaping the aforesaid cornerpiece, made for instance from sheet metal, comprises the steps ofshaping said sheet metal by pure folding substantially without anyelongation of the material, carried out by driving in a portion of thesheet metal, attended simultaneously by a concomitant free motiontowards each other of the non-deformed portions or layers of sheet metallocated on either side of the folding line, transversely of the latter,by an amount determined by the portion driven in. The method accordingto the invention provides an improvement over the state of the art inthat it consists in first forming the aforesaid dihedron by means of aprevious folding operation and then in carrying out, in a singleoperation, the forming of the aforesaid corrugations and of their commonconnecting surface.

The invention will be better understood and other objects,characteristics, details and advantages thereof will appear as thefollowing explanatory description proceeds with reference to theaccompanying diagrammatic drawings illustrating the corner piecedisclosed in the aforesaid copending divisional U.S. patent applicationand wherein FIG. 1 is a perspective view of the corner piece to be madeby the method according to the invention, the dihedral angle of whichforms substantially a right angle FIG. 2 is a diagrammatic profile orside view of a cor.- ner piece with an obtuse dihedral angle and FIG. 3is a diagrammatic view of the piece of FIG. 2 developed in a singleplane showing the various folding lines.

Since the corner piece shown in the drawing has already been fullydescribed in the aforesaid divisional patent application, it need not bedescribed again or further herein.

According to the invention, the method of manufacturing the corner piece1 from a metal sheet for example comprises shaping said sheet metal bypure folding or bending without any elongation or strain of thematerial. Said folding is carried out by driving in a portion of themetal sheet to form the corrugations or flutes 2, 2 while simultaneouslyfreely moving towards each other, in the direction of the straight lineZ-Z' or 3 those non-deformed portions la, lb, l'a, lb of the metal sheetwhich are located on either side of the folding, crest or ridge line 4,4', transversely of the'latter, by an amount determined by the depth orraised height of the driven in portion.

A significant feature of the process according to the invention consistsin first forming'the dihedron having an angle 0 by means of a previousfolding operation whereby the sheet 1 is bent about the axis Z-Z andthen in carrying out, in a single step, the forming of the corrugations2, 2 and of their common connecting surface ABCA'B'C.

A compression or contraction effort is exerted on said metal sheet Isubstantially in the plane of the sheet and in parallel relation to theedge line 3 of said dihedron in order to promote a combined shorteningof the metal sheet 1 and the'formation of the corregations 4,4.

Finally a substantially central imprint, hollow or depression 4a ofapproximately dihedral shape is impressed subsequently in theintermediate projecting di- It is to be understood that the inventionshould not be construed as limited to the embodiments described andshown which have been given by way ofillustration only, as manymodifications and alterations may be resorted to by those skilled in orconversant with the art without departing from the gist or scope of theinvention. In particular it comprises all the means forming technicalequivalents to the means described as well as their combinations, ifthey are carried out or put into practice according to the spirit,principles and teachings of the invention as defined in the appendedclaims.

What is claimed is:

1. A method of making a dihedron-like corrugated corner element of thecharacter described from a sheet of material, comprising the steps ofpreviously forming said dihedron by means ofa folding operation, andthen carrying out in a single step, the shaping of at least one 4 pairof inward projecting mutually registering corrugations extendingtransversely of and meeting on the edge line of said dihedron and thesimultaneous shaping of a common surface interconnecting saidcorrugations endwise.

2. A method according to claim 1, wherein a compression effort isexerted simultaneously upon the said sheet, substantially in the planeof the sheet and transversely of the direction of the said corrugationsi.e. in parallel relation to the edge of the said dihedron in order topromote a corresponding shortening of said sheet.

3. A method according to claim 2, wherein subsequently a depression isimpressed in an intermediate projecting dihedral portion of said commonsurface interconnecting said corrugations endwise.

1. A method of making a dihedron-like corrugated corner element of thecharacter described from a sheet of material, comprising the steps ofpreviously forming said dihedron by means of a folding operation, andthen carrying out in a single step, the shaping of at least one pair ofinward projecting mutually registering corrugations extendingtransversely of and meeting on the edge line of said dihedron and thesimultaneous shaping of a common surface interconnecting saidcorrugations endwise.
 2. A method according to claim 1, wherein acompression effort is exerted simultaneously upon the said sheet,substantially in the plane of the sheet and transversely of thedirection of the said corrugations i.e. in parallel relation to the edgeof the said dihedron in order to promote a corresponding shortening ofsaid sheet.
 3. A method according to claim 2, wherein subsequently adepression is impressed in an intermediate projecting dihedral portionof said common surface interconnecting said corrugations endwise.